Abdul Wahab

Senior Backend Developer

AIO • Full-time

Jun 2023 - Present • 3 yrs 2 mos

Led a 5–10 engineer POS squad, owning the end-to-end order-to-payment workflow with Stripe and Adyen integrations across 20+ tenants. Reduced billing API latency by 80%, from 1,000ms to 150ms, by eliminating redundant database calls across 20+ tenants. Resolved 10+ critical PostgreSQL performance bottlenecks in production using EXPLAIN ANALYZE, query optimization, and query restructuring. Designed and implemented BullMQ-based job queue processing, handling 1,000–10,000 background jobs daily across a distributed system. Architected a multi-tenant PostgreSQL data isolation layer supporting 20+ enterprise clients, maintaining strong data separation and zero security incidents. Implemented Redis caching and session management, reducing database read load by 20–50%. Automated stakeholder reporting using cron jobs and complex SQL queries, saving 5+ hours of manual work per week. Established PR review standards and ESLint rules across a 5–10 person engineering squad, improving code quality and consistency.

Backend Developer

Software Engineering Daily • Full-time

Aug 2021 - Jun 2023 • 1 yr 10 mos

Designed and shipped 20+ REST APIs with NestJS, Serverless Framework, and Express.js across 3 client projects Raised unit test coverage to 85% across core services, reducing regression bugs in CI/CD Integrated RabbitMQ for async communication across a microservices mesh on AWS ECS Provisioned fully serverless infrastructure (Cognito, DynamoDB, Lambda, S3, CloudWatch) for 3 production systems Investigated and resolved production incidents using CloudWatch logs in coordination with DevOps